Imidazolyl Poly(ionic liquids) Lubricant with Intelligent Current-Controlled Friction Performance

Smart lubricants are essential for the continuous control of smart devices. However, classic ionic liquids have struggled to meet the demands for real-time control of tribological behavior and long-term durability in smart devices. First, three poly(ionic liquids) with different chain lengths were synthesized through ionic liquid polymerization, and their structural morphology was characterized. The poly(ionic liquids) has better friction reduction and antiwear performance compared to its monomer. Under electrical stimulation, the friction boundary layer is strengthened, leading to an enhancement in the friction reduction performance. Furthermore, real-time control of the friction state can be achieved through electrical stimulation. Finally, the friction films at their friction interfaces were comprehensively characterized, and the underlying mechanisms were analyzed. This work opens possibilities by synthesizing imidazole-based poly(ionic liquids) as smart lubricating materials.